Carbon Dioxide and Earth's Future Pursuing the ... - Magazooms

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which is exactly what the symbiont shuffling hypothesis would predict. Hence, they further
stated that “this result demonstrates the importance of understanding the ecological history of
reefs (i.e., the chronology of disturbances) in interpreting the specific impacts of a particular
disturbance.”
In the same year, Brown et al. (2002) published the results of an even longer 17-year study of
coral reef flats at Ko Phuket, Thailand, in which they assessed coral reef changes in response to
elevated water temperatures in 1991, 1995, 1997 and 1998. As they described it, “many corals
bleached during elevated sea temperatures in May 1991 and 1995, but no bleaching was
recorded in 1997.” In addition, they report that “in May 1998 very limited bleaching occurred
although sea temperatures were higher than previous events in 1991 and 1995 (Dunne and
Brown, 2001).” What is more, when bleaching did take place, they say “it led only to partial
mortality in coral colonies, with most corals recovering their color within 3-5 months of initial
paling,” once again providing real-world evidence for what is predicted by the symbiont
shuffling hypothesis.
The following year, Riegl (2003) reviewed what is known about the responses of real-world
coral reefs to high-temperature-induced bleaching, focusing primarily on the Arabian Gulf,
which experienced high-frequency recurrences of temperature-related bleaching in 1996, 1998,
and 2002. In response to these high-temperature events, Riegl noted that Acropora -- which
during the 1996 and 1998 events always bleached first and suffered heaviest mortality --
bleached less than all other corals in 2002 at Sir Abu Nuair (an offshore island of the United
Arab Emirates) and actually recovered along the coast of Dubai between Jebel Ali and Ras
Hasyan. As a result, Riegl wrote that “the unexpected resistance of Sir Abu Nuair Acropora to
bleaching in 2002 might indicate support for the hypothesis of Baker (2001) and Baker et al.
(2002) that the symbiont communities on recovering reefs of the future might indeed be more
resistant to subsequent bleaching,” and that “the Arabian Gulf perhaps provides us with some
aspects which might be described as a ‘glimpse into the future,’ with ... hopes for at least some
level of coral/zooxanthellae adaptation.”
In a contemporaneous paper, Kumaraguru et al. (2003) reported the results of a study wherein
they assessed the degree of damage inflicted upon a number of coral reefs within Palk Bay
(located on the southeast coast of India just north of the Gulf of Mannar) by a major warming
event that produced monthly mean sea surface temperatures of 29.8 to 32.1°C from April
through June of 2002, after which they assessed the degree of recovery of the reefs. They
determined that “a minimum of at least 50% and a maximum of 60% bleaching were noticed
among the six different sites monitored.” However, as they continued, “the corals started to
recover quickly in August 2002 and as much as 52% recovery could be noticed.” By comparison,
they noted that “recovery of corals after the 1998 bleaching phenomenon in the Gulf of
Mannar was very slow, taking as much as one year to achieve similar recovery,” i.e., to achieve
what was experienced in one month in 2002. Consequently, in words descriptive of the
concept of symbiont shuffling, the Indian scientists said that “the process of natural selection is
in operation, with the growth of new coral colonies, and any disturbance in the system is only
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